Telephone companies have been installing small cell antenna systems, or “small cells,” to increase geographical cell network coverage. Small cells are generally low-powered cellular radio access nodes that operate in the licensed and unlicensed spectrum that have a range of 10 meters to a few kilometers. These companies have been installing the small cells on existing electrical power poles (wood or metal), particularly poles that are situated in cities, as they do not need to pay rent as would be the case with other placements of such antennas at commercial establishments.
Each small cell antenna system generally includes a cellular radio (or transceiver), radio frequency (RF) conditioning equipment (e.g., diplexer, triplexer, multiplexer, etc.), a network interface, and an antenna, all of which are commercially available devices. The antenna is located at or near the top of the pole. The radio, RF conditioning equipment, and network interface are situated in a shroud below the antenna. A coaxial cable connects the antenna to the RF conditioning equipment, which in turn, is connected to the radio. The RF conditioning equipment multiplexes, demultiplexes, and filters signals at different disjoint frequencies or frequency bands so that multiple frequency channels pertaining to a plurality of radios can be used with the single antenna. The network interface essentially interfaces the radio with a network associated with a carrier. For instance, the network interface could be an optical fiber associated with a fiber optic network.
Currently, the shrouds house up to two radios, but they must be of the same type. Better designs for shrouds are needed.